The invention relates to injection therapy catheters which are typically employed through a working channel of an endoscope to inject fluid agents to sites within the body.
As is known in the art, such a catheter which slidably supports an extendable and retractable needle catheter, can be employed, to provide treatment to a bleeding area, for example, an ulcer in the gastrointestinal tract or the site of esophageal varices. With such treatment, drugs such as sclerosing or vasoconstrictive agents are administered to the treatment area to clot or occlude the bleeding tissue to stop bleeding or to reduce the possibility of a blood vessel bursting.
It is not uncommon for blood or other obscuring substances to obstruct the visual path at the observation port located at the distal end of the endoscope. In such circumstances, the physician's ability to accurately position the catheter is hindered. One approach for clearing the worksite is to remove the drug administering catheter and provide a separate irrigation catheter to wash away the obscuring material. The drug administering catheter is then reintroduced to the target site.